How Dangerous Is the Deathstalker Scorpion? Venom and Risk

How potent is deathstalker venom?

The deathstalker (Leiurus quinquestriatus) belongs to the family Buthidae, which contains nearly all the scorpions that are dangerous to people. Its venom is a mixture of many small proteins, mostly neurotoxins that interfere with the channels nerve cells use to send electrical signals.

Scientists compare venoms using the median lethal dose (LD50), the amount that kills half of the laboratory mice tested. For the deathstalker, published values are about 0.16–0.50 mg per kg of body weight, among the lowest, and therefore most potent, figures recorded for scorpions. Values vary with the method used and the population tested, which is one reason different sources disagree about which scorpion is “the most venomous.”

A low LD50 in mice does not mean every sting is deadly to a person. The amount of venom injected matters just as much. A scorpion may deliver a full dose, a small one or, in some defensive stings, almost none.

What happens after a deathstalker sting?

The first and most common symptom is pain. It starts immediately and is often described as burning or stabbing, sometimes with tingling and numbness spreading from the sting site. There may be little visible swelling.

In more serious cases, the venom affects the whole body. The toxins overstimulate the nervous system, which can cause sweating, drooling, vomiting, restlessness, muscle twitching, a fast or irregular heartbeat and high blood pressure. In the most severe cases the heart is weakened and fluid builds up in the lungs, a condition called pulmonary edema, which is the usual cause of death after a fatal sting.

Severe symptoms typically develop within the first hours. This is why any sting by a deathstalker, or by any unknown scorpion in a region where dangerous species live, is treated as a medical emergency.

Who is most at risk?

Young children are by far the most vulnerable. A scorpion injects roughly the same amount of venom whatever the size of the victim, so a toddler receives a much higher dose relative to body weight than an adult does. Children also develop body-wide poisoning more often and more quickly.

Older adults and people with heart disease, high blood pressure or breathing problems are also at higher risk, because the venom puts strain on the heart and lungs. As with bee and wasp stings, a small number of people may also have an allergic reaction to the venom, which is a separate emergency.

For healthy adults, a deathstalker sting is usually an extremely painful experience rather than a fatal one, especially where good hospital care is available.

How common are stings and deaths?

Scorpion stings are a serious public health problem in parts of North Africa, the Middle East, India and Latin America. A global review published in 2008 estimated more than one million scorpion stings each year worldwide and several thousand deaths, most of them children. These numbers are estimates, because many stings are never reported.

The deathstalker is only one of several dangerous species in its region. Fat-tailed scorpions of the genus Androctonus and some Buthus species also cause serious stings in North Africa, and stings are often blamed on whatever scorpion is best known locally. Reliable figures for deaths caused by the deathstalker alone are therefore hard to give.

How does it compare with other dangerous scorpions?

The Arizona bark scorpion is the most venomous scorpion in the United States, but stings rarely lead to severe illness in adults, as explained in is the Arizona bark scorpion deadly?. The deathstalker and its African and Middle Eastern relatives cause severe poisoning more often. For a wider view, see our list of the most venomous animals.

How stings happen and how to stay safe

Deathstalkers do not chase or attack people. They are nocturnal and spend the day hidden under stones, in burrows or in cracks in walls. Most stings happen when someone puts a hand under a rock, walks barefoot at night, or puts on a shoe or piece of clothing where a scorpion is sheltering.

The safest approach in deserts where these scorpions live is simple respect: never handle a scorpion, watch where you put your hands and feet, and do not disturb scorpions you find. If anyone is stung, especially a child, seek emergency medical help immediately or call the local emergency number (112 across the EU, 911 in the US, 999 in the UK).

Can the venom also help people?

Remarkably, the same venom has become valuable to medicine. One of its proteins, chlorotoxin, binds to certain brain tumor cells much more than to healthy brain tissue. Researchers have attached glowing dyes to modified chlorotoxin so that surgeons can see tumor cells more clearly during operations, and these “tumor paint” products have reached clinical trials. Other deathstalker toxins are widely used in laboratories to study how nerves and muscles work.